The goal of this proposal is to determine the feasibility of using microwaves for the burnout cycle of the dental casting procedure. Microwaves effect materials by generating heat throughout the material, rather than by relying upon thermal conduction. The heat is generated primarily by the dielectric power loss as polar molecules within the material try to align themselves with the alternating electromagnetic waves. This type of heating offers the promise of rapid, uniform heating of non conductive materials containing polar molecules, such as dental wax and dental investment. To evaluate the feasibility of using microwaves, the following data will be obtained in this study: (1) temperature obtainable by heating of these materials, (2) time to reach these temperatures, (3) variables effecting optimum time-temperature relation, (4) degree of wax elimination, (5) thermal expansion and (6) effect on final casting. No information concerning this application of microwaves in the health profession has been published. This study will provide heretofore unavailable information concerning the feasibility of using microwaves for heating of commercially available dental was and investment, and what direction future modifications should pursue to improve its feasibility.